Method of making shoe-filler



July 26, 1932.

A. THOMA METHOD OF MAKING SHOE FILLER Filed Sept. 27, 1929 m w a jPatented July 26, 1932 ANDREW. THOMA, OF CAMBRIDGE, MASSACHUSETTS,ASSIGIIOR TO NORTH AMERICAN.

PATENT OFFICE CHEMICAL COMPANY, OF CAMBRIDGE, MASSACHUSETTS, ACORPORATION OF MASSA:

CHUSETTS METHOD OF MAKING SHOE-FILLER Application filed September 27,1929. Serial No. 395,665.

This application is for the process of mak ing the product claimed in mycopending application Serial No. 395,664 filed September 27, 1929.

The advancing requirements of shoe manufacture and especially of presentstyles, call for lightness of the plastic or spreadable shoe filler andpermanency, almost stiffness in fact, when in its ultimate spread andlaid condition inthe shoe-bottom cavity of the finished shoe.Accordingly my present invention is a method of providing extremelightness, stiffness and permanency as well as reduced cost in the shoefiller by employing as a considerable part of the bulk giving portion ofthe filler light weight binder and body material. The binder, waxtailings, heretofore commonly employed, has been Very heavy. One of thestriking novelties of my invention is not only to employ chiefly a lightweight binder, but to employ said binder in the dual capacity of bothbody material and binden. This accomplishes the use of a largeproportion of said light weight'material and it accomplishes variousother unexpected advantages. In other words my new filler consists ofbody material, body-binder-material, and binder; To this end I employthe ,hard kinds of binder materials, especially the hydrocarbons, suchas rosin, resin gums, asphalts, bituminous materials, and the like, andI preferably employ these in the form of ground particles orgranulations instead of in a melted condition as always heretofore. Forexample certain grades of rosin are lighter in weight or of higherspecific gravity than certain grades of cork. For accomplishing thelight weight feature of my in vention. I select therefor the lightweight binder material and of such a hardness that it can be ground thesame as the cork or other inert or woody matter. preferably grinding thetwo together, or otherwise providing the hard binder material indecimated form or granulations of proper size to function as bodymaterial and as the latent binder portion of the filler mass, giving"both bulk an Quality to th structural cons stency of the fillercommercially and then later in use.

In making my filler, the woody or comminuted fibrous portion of the bodymaterial 1s preferably first soaked in hot water, s01- uble Oll, soapsolution, and/or any of the gas or steam or ebullition producingconstituents.

ments and aids in the subsequent rapidity of the shoe-bottom fillingoperation. Heat, dry, moist or wet, or the gas or other expansionmeansjust mentioned constitute other means and steps toward the same ends.The preliminary soaking ofthe fibrous body-material is to conduce toultimate lightness by first swelling or distending the cork and theninterposing therein this barrier to prevent the otherwise inevitablesoaking of the cork or loading thereof with the heavy, sluggish soft waxtailin gs. Also the oiled or solubleoil-containing cork or otherabsorbent body material is more lively, resilient, tough. more easilyspread. more easily conditioned (because more readily absorbent orresponsive to steam or'to melted binder, even if sealed) than natural ordry cork (untreated) which is dead, dry, brittle, etc. Still furtherlife. resilience and lightness is preferably secured by fixing the soapysolution or the like in the cork permanently, which may be done byintroducing any reacting agent such as a preferably weaksolution ofsulphate of aluminum. The reacting agent precipitates the soluble fattyacid radical such as the soap solution, into an insoluble aluminumstearate. Asa generic term for the treatment with, oil, grease, fat,soap and the like I refer to it as a conditioning with unctuoussubstance or as an unctuous treatment. Preferably the aforesaid fixingor setting step takes place before thebinder is introduced, but it may b'later, the setting agent then being mixed in as dry powder into thebinder, to be rendered active by the subsequent steaming step in layingthe filler, or it may lT-Q'lHiJYOClUCSCl as a liquid setting or reactingagent whenever desired. The comminuted body-material, preferably fibrousand preferably soaked, swelled, and set as. thus ex panded, to promoteresilience and lightness, is then sprayed or otherwise coated with hotfluid resins or any of the hard hydrocarbons already mentioned,preferably also the high gravity or very light Weight kinds, preferablywhile the comminuted body material is being agitated in a mixer. Thispromotes still further lightness of the final filler. By this processeach granule or particle of the finely ground woody or mineral matter orother comminuted body material is provided with a very thin fine coat ofthe hard high melting material which instantly sets hard as it strikesthe granules. in such case, the coating is preferably heavy and, whetherthe bodyparticles have uniform size or not, the desired evenness maybesecured by sieving or forcing the coated particles, slightly warm,through a desired mesh. This pro vides a finely coated body materialwhich is at least partly high-heat responsive. Then this body materialis united into a sticky mass by being mixed with as thin a coating aspossible of low melting sticky wax tailings or any'of the other stron lysticky and permanently plastic, adhesive and coherent low meltingbinders. The low melting soft wax tailings is preferred and is in a hotand very fluid condition when being intermixed with the coated bodygranules so as to envelope the granules thinly and yet suiiicientlytohold the mass together as a coherent body, capable of being shapedinto a commercial parcel for shipping, storing and general handling. Theamount of this very soft and easily fluid binder may be largely variedaccording to the proportion of granular hydrocarbons and the like whichare next introfibrous body material and the soft or low melting waxtailings or other hydrocarbons, I introduce into the mixer therewithhard hydrocarbons of the kind or kinds previously menti oned,preferablyof the very lightweight variety or varieties, said hard material beingin dry ground particles or granulations.

This granular mass of hard binder materialin a wholly unmeltedconditionor inherently dry, is then mixed thoroughly into and throughout thestill warm and miscible materials which. have just been mixed together.The result is that the small chunks or particles of hard binder materialin their ground or broken condition are incorporated as thoroughlythroughoutthe filler mass as the fibrous or other body material. Thegranules of binder mater al now occupy the position of body materialside by side with the other body material throughout the mass. Underordinary heat these granules are incapable of acting as binder but onlyas body material. In other words as the active binder or low melting waxtailings responds readily to low heat, it-will be seen that my inventiongreatly assistsat the shoe factory in getting the filler mass soft foruse. It quickens or speeds up the conditioning step. Likewise it is mucheasier to spread. Thus it saves time and heat. Also it is low cost.Likewise it can be made very light weight, depending on the coating oflatent high-heat-responsive stiffener and also on the ground orgranulated hard latent binder to furnish both the necessary volume (bodymaterial) and also the necessary high grade binding quality for the laidmass as will presently be explained. To still further promote the quickstiflening and the lightness of the laid filler I introduce into thesoft wax tailings binder powdered rosin, asphalt or other dry latentbinder. Before the mixture has hardened or set, and while it is stillsoft, I preferably incorporate the same by blowing said powder on thesoft binder coating or into the soft wax tailings binder, preferablyduring the mixing process, finely decimated hard binder material such asthe asphalt, hydrocarbons and the like already mentioned. This forms thedouble office of constituting a dulling powder to reduce the massquickly to a dough-like stability and also it introduces the highmelting point element already explained. Such dry or hard bindermaterial, whether as chunks, coatings, powder or the like, I termbodybinder. It constitutes body-material or is simply a space-occupierunless and until fused in the use of the filler. T he functioning of thebody-binder material, or such portion thereof as is ultimately melted inthe process of filling the shoe-bottom cavities, as a high grade binderand stiffener does not take place until the filler has been actuallyplaced in the shoe. Then the deposited filler is subjected to a suddenhigh heat preferably by a super-heated spreading roll. This momentaryextra melting heat fluxes 0r fluidifies the hard ground coating and alsothe particles or granulations of body-binder that the roll comes incontact with and the simultaneous flowing or filler-spreading act unitesthe same throughout the laid filler so that the suddenly melted andunited ingredients, which previously ramified the filler as separatedparticles and as inert chunks, now ramify the layer as a unitedstiffener as soon as the high heat is removed. On the other hand, theunfused particles and chunks and coatings remain as space-occupiers orsimply body-material. As the hot roll flows the filler with itsspreading action.v the roll comes in contact with more or less of thehard parti cles throughout the mass, melting the same and flux ng themwith the soft binder and causing them to stick likewise to the rest ofthe body material. By the same means and act the sudden high-heatlikewise melts or softens more or less of the hard coatings so far asthe super hot tool contacts therewith, which cooperates with the rest ofthe melted and fiuxed binder to insure positive, direct and permanentgripping together of all the body particles into one strong, stiffenedbut yet flexible, homogeneous sheet or spread layer of filler throughoutthe'cavity. The body material consists now of both the woody particlesand such of their coatings as have not been fused but still remain suchand also such of the hard particles of binder material as may not havebeen fused. I refer to this new kind of body material as body-bindermaterial. The final laid filler in the finished shoe has a permanency,stiffness (i. c. it is rigid and nonstretchable) and hardness heretoforeimpossible, and is thereafter not subject'to bunching or shifting and isnot amenable to low heat such as a shoe would ever be subjected to inuse. The particular hard binder that I prefer is blown asphalt. This isa residuum petroleum of the beltic base variety treated until it issubstantially saturated with oxygen or at least until its character ischanged into permanent flexibility or pliability so as to eliminate itsnatural brittleness by becoming toughened by oxygenating treatment tothe extent known by the name in the trade of blown asphalt. I have foundthis material has remarkable and unexpected advantages in carrying outmy invention. A shoe bottom filler piece made with this blown asphaltis'non-sticky externally as an article of manufacture, softens andreadily becomes spreadable, and, under the sudden high heat treatmentexplained, becomes permanently pliable when thus laid in the shoebottom, never becomes liable to bunch, is very strongly adherent toleather, so that the blown asphalt layer can never shift in the shoebottom, is not responsive so as to soften under any heat to which theshoe would be exposed in use, is tough and durable beyond the ordinarylife of the shoe, needs no backer and strengthening element as a fillercomponent within or on the piece, is cheap, without waste in manufactureand use, and is always clean.

If preferred, the spraying or coating of the fine woody particles orother comminuted body-material may be omitted, depending upon thesubsequent step of the application of the sudden high heat tounite theparticles by means of such of the hard particles of bind er as arethereby melted and forced into gripping on, "emont with the woody orother particles the layer is spread. In

' such case the comminuted body material,

preferably first wetted or and pretreated alrea explained, is unitedinto the desired pro 'n .y sticky mass by lie-- interm xed with the softor low meltin binder, preferably wax tailin gs, and the rd chunl-ls orparticles of hydrocarbon or the are once mire d into the st til thelatter is ky mixture unor doughy the same before, and/or powd red latentbind-era's blow into the mass being mixed or is otherwise introduced. Orthe hard binder may be secured sufficiently by a heavier spraying andthe introduction of the hard, high-heat particles. dry maythen beomitted. in all these ways I add a firmer filler mass to a softer fillermass to make the complete shoe-filler. The method of use'of such filleror method of filling shoes therewith is claimed in my copendingapplication Ser. No. 338,320 filed Aug. 26, 1929.

The natural absorption of the soft wax tailing's by the cork or the likeis prevented by the moistening of the cork or the saturation thereofwith the repelling water, soap,

etc, and preferably the cushioning stearate precipitate, and the suddenhigh heat tends to convert some of this repelling moisture into steamthereby facilitating the spreading movement, but as the high heatapplication is so momentary, and the soft wax tailings binde ispreferably only such a thin coa g mply to hold the parts together (inthe preferred embodiments mentioned), the cork or other fibrous materialis ultimately left very porous. Some of the water is left to evaporatelater and to be absorbed by the adjacent leather. The hard or stiffeningbinder grips the cork particles tenaciously, being much more stronglytenacious than the binders heretofore used or heretofore possible to useby previous methods, and hence the cork particles, having parted withtheir absorbed water or the like, are held in a porous open condition bythe set, tenacious stiffener of the binder, thereby further conducing tothe light weight character of the finished layer. This is especiallymarked in case the fatty content (soluble oil or soap) is set as aninsoluble stcarate b y the sulphate of aluminum treatment at the startor later in the process. Even the operator subject-s the filler layer tosuch pressure as to produce more or less contraction, nevertheless myprocess leaves the filler mass semi'porous and more porous than before.Other dry inert material may be intro duced along with the dry bodybinder material capable of being developed by the sunden high heat stepinto an additional firming or stiffening ingredient. Such ingredientsmay be ground along with the body material and hard hydrocarbons andintroduced into the filler mass therewith the same as already explained.Also pulverized or granulated dulling powders may be introduced. In factI wish it understood that the final filler may embody most of thefeatures set forth in my copending application Ser. No. 297,630 abovereferred to.

Summarized, my invention comprises, in this preferred embodiment, thefollowing features. I depend merely on the old method of making fillerwith ground body material and binder to furnish the foundation base formy new filler and I incorporate therewith latent matter which isdeveloped as a stiffener to the extent determined by the operative atthe time of actual installation of the filler as a layer in theshoe-bottom cavity. Preferably the sticky element in the filler, as anarticle of manufacture, is a minor element to be largely reinforced forstrength and stiffness by the latent matter later at the time of fillingthe shoe-bottom cavity. Also my method is new in the broadest sense inproviding the filler with a body forming mass within the compound of anykind which is capable of functioning both as a binder and as a bulk bodyformer. Whether it functions as one or the other depends on whether ornot it is fiuxed at the time of being laid in the shoebottom. This maybe accomplished in various ways but preferably while it is pressedagainst or by a super-hot levelling tool or roll. Such portion of thislatent body-binder material as does not flux or come into actual fiuxingcondition or contact, remains as before the heat rolling process, aparticle or portion of the body forming part of the filler. The same istrue of the body-bindcr which may be set as a coating by the spraying orother applying process. My invention therefore makes it possible for theoperative to determine the relative proportion of stifiness and therelative proportion of body material. If he Wishes the ultimate cavitylayer to be extra stiff he maintains the heat at such a very hightemperature or in contact with the filler such a period of time as willmelt and flux a greater portion of the body-binder ingredient or of thehigh-melting point ingredient or component, which thereupon sets at oncewhen the heat is removed and leaves the laid filler in a permanentlyextra rigid condi tion. If he wishes a more flexible and less rigidfiller layer in the cavity, he does not apply as much heat or applies ita shorter pe riod. I prefer to employ ,round cork or other fibrous bodyforming material along with the body-binder material as it makes a moreresilient cavity layer, but this fibrous material may be omitted and theentire body material of the filler may be body-binder. Gther featuresand details of my invention are set forth elsewhere herein and in theappended claims.

In order to present my method more visually distinct I refer to theaccompanying drawing in which Fig. 1 shows in section a piece of bulkfiller made according to my method;

Fig. 2 shows a section of a died-out filler piece embodying myinvention;

3 is an enlarged or magnified section of a cork granule sprayed asexplained; and

F 4 is a sectional view of a mass or bulk of filler made in connectionwith the spraying step. 7

Referring to the drawing, F 1 shows a bulk or mass of filler 1 composedof ground cork or other uusual fibrous or other com- Fig.

minuted body material 2, preferably soaked and so treated, as explained,as to remain distended and light-Weight (the stearate treatment), someor all of which particles have a coating 3 of high-melting-point bodybinder material of any of the hard kinds previously mentioned. Thesecoated particles are surrounded or mixed in with wax tailings or othersoft binder 4, preferably dulled with powdered latent binder orbody-binder. I then intermix with the foregoing elements 2, 3 and 4ground or comminuted dry particles 5 of high heatresponsive body binder.

The step of setting the cork, or the precipitation and othercork-treatment previously mentioned, is preferably accomplished beforemixing the filler. In fact, it may be long before, and the cork thendried and stored for later use. Or it may be accomplished at the period.of mixing, or when filling the shoebottom cavity, in which latter casethe precipitating agent is contained in the filler in an inactivecondition and rendered active by the steaming of the filler forspreading or by the water pressed from the cork, for example, by thespreading roll or by the leveller. Also the requisite chemicals for thissetting or fixing treatment, as already explained, may be provided inconnection with treating the cork or treating the binder, and in eithercase the filler may be mixed either before or after the fixing orsetting takes place. Certain other phases of this general subject arecontained in my applications Ser. No. 336,908 filed Feb. 29, 1929 andSer. No. 389,872 filed Aug. 31, 1929.

In Fig. 3 I have shown a granule 6 of cork (or, as previously explained,it may be a granule of rosin or any other body binder material in chunkor dry solid fragmentary form), greatly magnified, in order to show thethin film or covering 3 of the hard body binder as it is sprayed thereonin a spray 7 from a nozzle 8. It will be understood that I have simplyindicated conventionally the apparatus, as spraying nozzles forliquefied substances which are normally solid are well knowncommercially.

In Fig. 2 the same elements are shown in the form of a filler piecemoulded into a shape-maintaining coherent and compressed self-supportingpiece as an article of manufacture, containing a predetermined volumefor filling a single shoe-bottom as set forth and claimed in myapplication Ser. No. 297,630 aforesaid. Fig. 2 shows this piece havingthe latent stiffener or body binder material 5 denser in the upper part,so that when a high heat tool, preferably a roll as indicated at 9, ispressed down thereon, as shown in Fig. 2, more or less of the material 5is suddenly melted and flowed along with the rest of the spreading pieceand intermingled and spread more intimately with the body materials 2, 3to give strength, permanency and stiffness to the filler layer as itfinally exists in the shoe-bottom cavity. This method of use iscontained in my aforesaid application Ser. No. 338,320. If the coatedparticles are present as shown, some of their coatings are melted bycontact with the roll 9 and serve, upon setting, to hold the layertenaciously together as well as stiffer. As already explained, thefiller, in bulk or in piece, may omit various of the elements and bemade with the various combinations ofelements previously mentioned,according to the particular advantages, economies and requirements ofdifferent grades and kinds of shoes and conditions of use and othercircumstances.

For example, Fig. t shows a filler mass 10 as made in connection withthe spraying step, the sprayed granules being united by soft binder ithe same as in Figs. 1 and 2 to constitute the bulk filler or it may bethe piece embodiment if preferred.

This application is a continuation in part of my previously mentionedapplications where the advantages of hard, tenacious, high melting pointmaterial are set forth, particularly the high melting point asphalts,and where the formation of the filler into a selfsupporting spreadablepiece of standardized shape and other detailed construction is explainedat greater length and duly claimed. I there enter into greater detail asto the advantages and disadvantages of the low melting variety ofhydrocarbon binder, especially of a paraffin base and its advantage inconnection with hard asphalts or other high melting hydrocarbons inaiding the laying by preventing the heated laying tool from stickingunduly, and also point out that when made in a finished dense individualpiece even with a crust, top layer or upper portion of high-meltingmaterial as in Fig. 2 herein, the danger of smooching and staining andtool clinging are minimized or eliminated. Because of their high meltingpoint, materials of the nature of asphalts having 150200 melting pointcould not be used in mass in a kettle or usual filler apparatus asheretofore practiced with plastic fillers of the present day andearlier. The reasons are set forth in more detail in my copendingapplication Ser. 838,320 aforesaid. The latter application also setsforth a method which requires extra high heat for the preliminarysoftening of the piece to make it spreadable properly in the shoe-bottomcavity, the latter also requiring more or less heat. Accordingly I haveomitted to set forth herein the wide range of variations in materialsetc. because the same are set forth and explained fully in the aforesaidtwo copending applications. The preferred embodiment of my filler, asherein set forth, is readily influenced by low heat for its preliminaryconditioning, and hence simply requires for said preliminary softening avery low-heat pan like a glue pot or culinary cooker where the heatedwater jacket prevents injury or undue heating of the filler mass whilemaintaining it sufficiently soft for the operator to lift into theshoebottom and then apply the second step, viz.

the super-heating by means of a spatula, such for instance as shown inmy Patent No. 87 8,688 of February 11, 1908.

I claim:

r 1. The art of making heat plastic, spreadable, shoe-bottom filler,which comprises melting a soft, sticky, cementitious, lowheat meltingpoint binder, and mixing but not fusing with said melted low-heatmelting point binder, hard high-heat melting point body binderselectedfrom the group consisting of asphalt, rosin, resin gums, bitumen andhard hydrocarbon, in the form of small, discrete, segregated units in adry, hard state, thereby to produce a heat plastic filler mass capableof being sufiici-ently softened for spreading in a shoe bottom cavity bylow heat adapted to soften the soft binder without softening the hardbody binder, the hard body binder being adapted to be softened andblended with the soft binder by the sudden brief application of highheat.

2. The art of making heat plastic, spreadable, shoe-bottom filler, whichcomprises melting a soft, sticky, cementitious, low-heat melting pointbinder, and mixing but not fusing with said melted low-heat meltingpoint binder, hard high-heat melting point binder selected from thegroup consisting of asphalt, rosin,resin gums, bitumen and hardhydrocarbon, in a dry, hard, comminuted state, thereby to produce a heatplastic filler mass capable of being sufficiently softened for spreadingin a shoe bottom cavity by low heat adapted to soften the soft binderwithout softening the hard body binder, the hard body binder beingadapted to be softened and blended with the soft binder by the sudden,brief application of high heat.

3. The art of making heat plastic, spreadable, shoe-bottom filler, whichcomprises preparing a comminuted, fibrous body material by coating itsindividual particles with hard, high-heat melting point binder selectedfrom the group consisting of asphalt, rosin, resin gums, bitumen andhard hydrocarbon, meltmg a soft, sticky, cementltious, low-heat meltmgpoint binder, and mixing said coated particles of body material withsaid melted lowheat melting point binder without fusing or blending thehigh-heat melting point coatings with the low-heat melting point binder.Signed by me at Cambridge, Massachusetts, this twenty-seventh day of July, 1929.

ANDREW THOMA.

